Separately: in the FOSS space - that is, independent community-led software, they also have different meanings.

FOSS Projects are the combination of the community and the general idea of a drive to improve some set of technology. Projects have governance - either explicitly led by a company, by a BDFL, or by an independent community like at Apache, Eclipse, and other foundations.

FOSS Products are discrete software products you can download or use. It's the software, not the people.

This distinction is doubly important when it comes to branding and trademarks. Your project name is probably not legally a trademark, unless you take steps to use it as such. Your product name is almost always a trademark, as long as you're consistent in it's proper use. Trademarks may not seem important when your project is starting it's first product, but they'll be very important if your technology ever turns into something businesses are interested in.

For more resources about how trademarks intersect with projects and products, see my resource list at the ASF's trademark pages: